Alex magnetometer and telluric station in Egypt: First results on pulsation analysis

Abstract

This study presents the first results of a newly installed ground-based station Alex Magnetometer and Telluric Station (AMTS) located in Alexandria governorate in Egypt (geographic coordinate: 30° 51.68′ N, 29° 33.67′ E). The station consists of a fluxgate digital magnetometer and a two-channel digital Long Period Telluric Recorder (LPTR). The station commenced operation on October 12th, 2021, by providing real-time data of the geoelectric and geomagnetic field components. Despite the low solar activity, the AMTS detected several signatures of geomagnetic storms. An illustrative case study was conducted on the strong geomagnetic storm of November 4th, 2021. The magnetic field components recorded by the station demonstrated a prompt increase synchronized with the Sudden Storm Commencement (SSC) captured by the ACE satellite arriving at 19:42 UT on November 3rd, 2021. The three geomagnetic field components recorded by the AMTS during the storm were consistent with the nearby INTERMAGNET stations. The digital fluxgate magnetometer’s high sampling frequency (400 Hz) and the LPTR with a sampling frequency (1 Hz), allowed us to capture all ULF pulsations. The structural pearl-shaped Pc1 pulsation was obtained in all phases of the geomagnetic storm with repetitive oscillations in the main storm phase. The wavelet analysis of micropulsations recorded at AMTS showed a high coherence with the nearby-four INTERMAGNET stations demonstrating high data integrity and reliability. The magnetometer and telluric measurements at the AMTS will fill the data gap in the northern section of Africa and allow us to study geoelectric and geomagnetic micropulsations in the region.